#include <iostream>
using namespace std;

int main()
{
    cout << "学号：3170608043，姓名：石英钰" << endl;
    int myScore;
    cout << "Please input your score: ";
    cin >> myScore;
    if (myScore < 0 || myScore > 100)
    {
        cout << "Invalid score: " << myScore << ", score should not be negative or greater than 100." << endl;
        return 1;
    }
    switch (myScore / 10)
    {
    case 10:
    case 9:
        cout << "The degree is A" << endl;
        break;
    case 8:
        cout << "The degree is B" << endl;
        break;
    case 7:
    case 6:
        cout << "The degree is C" << endl;
        break;
    default:
        cout << "The degree is D" << endl;
    }
    return 0;
}